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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 file guides

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1// Copyright (c) 2022-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <node/txreconciliation.h>
6
7#include <common/system.h>
8#include <util/check.h>
9#include <util/log.h>
10
11#include <unordered_map>
12#include <variant>
13
14
15namespace {
16
17/** Static salt component used to compute short txids for sketch construction, see BIP-330. */
18const std::string RECON_STATIC_SALT = "Tx Relay Salting";
19const HashWriter RECON_SALT_HASHER = TaggedHash(RECON_STATIC_SALT);
20
21/**
22 * Salt (specified by BIP-330) constructed from contributions from both peers. It is used
23 * to compute transaction short IDs, which are then used to construct a sketch representing a set
24 * of transactions we want to announce to the peer.
25 */
26uint256 ComputeSalt(uint64_t salt1, uint64_t salt2)
27{
28    // According to BIP-330, salts should be combined in ascending order.
29    return (HashWriter(RECON_SALT_HASHER) << std::min(salt1, salt2) << std::max(salt1, salt2)).GetSHA256();
30}
31
32/**
33 * Keeps track of txreconciliation-related per-peer state.
34 */
35class TxReconciliationState
36{
37public:
38    /**
39     * TODO: This field is public to ignore -Wunused-private-field. Make private once used in
40     * the following commits.
41     *
42     * Reconciliation protocol assumes using one role consistently: either a reconciliation
43     * initiator (requesting sketches), or responder (sending sketches). This defines our role,
44     * based on the direction of the p2p connection.
45     *
46     */
47    bool m_we_initiate;
48
49    /**
50     * TODO: These fields are public to ignore -Wunused-private-field. Make private once used in
51     * the following commits.
52     *
53     * These values are used to salt short IDs, which is necessary for transaction reconciliations.
54     */
55    uint64_t m_k0, m_k1;
56
57    TxReconciliationState(bool we_initiate, uint64_t k0, uint64_t k1) : m_we_initiate(we_initiate), m_k0(k0), m_k1(k1) {}
58};
59
60} // namespace
61
62/** Actual implementation for TxReconciliationTracker's data structure. */
63class TxReconciliationTracker::Impl
64{
65private:
66    mutable Mutex m_txreconciliation_mutex;
67
68    // Local protocol version
69    uint32_t m_recon_version;
70
71    /**
72     * Keeps track of txreconciliation states of eligible peers.
73     * For pre-registered peers, the locally generated salt is stored.
74     * For registered peers, the locally generated salt is forgotten, and the state (including
75     * "full" salt) is stored instead.
76     */
77    std::unordered_map<NodeId, std::variant<uint64_t, TxReconciliationState>> m_states GUARDED_BY(m_txreconciliation_mutex);
78
79public:
80    explicit Impl(uint32_t recon_version) : m_recon_version(recon_version) {}
81
82    uint64_t PreRegisterPeer(NodeId peer_id) EXCLUSIVE_LOCKS_REQUIRED(!m_txreconciliation_mutex)
83    {
84        AssertLockNotHeld(m_txreconciliation_mutex);
85        LOCK(m_txreconciliation_mutex);
86
87        LogDebug(BCLog::TXRECONCILIATION, "Pre-register peer=%d\n", peer_id);
88        const uint64_t local_salt{FastRandomContext().rand64()};
89
90        // We do this exactly once per peer (which are unique by NodeId, see GetNewNodeId) so it's
91        // safe to assume we don't have this record yet.
92        Assume(m_states.emplace(peer_id, local_salt).second);
93        return local_salt;
94    }
95
96    ReconciliationRegisterResult RegisterPeer(NodeId peer_id, bool is_peer_inbound, uint32_t peer_recon_version,
97                                              uint64_t remote_salt) EXCLUSIVE_LOCKS_REQUIRED(!m_txreconciliation_mutex)
98    {
99        AssertLockNotHeld(m_txreconciliation_mutex);
100        LOCK(m_txreconciliation_mutex);
101        auto recon_state = m_states.find(peer_id);
102
103        if (recon_state == m_states.end()) return ReconciliationRegisterResult::NOT_FOUND;
104
105        if (std::holds_alternative<TxReconciliationState>(recon_state->second)) {
106            return ReconciliationRegisterResult::ALREADY_REGISTERED;
107        }
108
109        uint64_t local_salt = *std::get_if<uint64_t>(&recon_state->second);
110
111        // If the peer supports the version which is lower than ours, we downgrade to the version
112        // it supports. For now, this only guarantees that nodes with future reconciliation
113        // versions have the choice of reconciling with this current version. However, they also
114        // have the choice to refuse supporting reconciliations if the common version is not
115        // satisfactory (e.g. too low).
116        const uint32_t recon_version{std::min(peer_recon_version, m_recon_version)};
117        // v1 is the lowest version, so suggesting something below must be a protocol violation.
118        if (recon_version < 1) return ReconciliationRegisterResult::PROTOCOL_VIOLATION;
119
120        LogDebug(BCLog::TXRECONCILIATION, "Register peer=%d (inbound=%i)\n",
121                      peer_id, is_peer_inbound);
122
123        const uint256 full_salt{ComputeSalt(local_salt, remote_salt)};
124        recon_state->second = TxReconciliationState(!is_peer_inbound, full_salt.GetUint64(0), full_salt.GetUint64(1));
125        return ReconciliationRegisterResult::SUCCESS;
126    }
127
128    void ForgetPeer(NodeId peer_id) EXCLUSIVE_LOCKS_REQUIRED(!m_txreconciliation_mutex)
129    {
130        AssertLockNotHeld(m_txreconciliation_mutex);
131        LOCK(m_txreconciliation_mutex);
132        if (m_states.erase(peer_id)) {
133            LogDebug(BCLog::TXRECONCILIATION, "Forget txreconciliation state of peer=%d\n", peer_id);
134        }
135    }
136
137    bool IsPeerRegistered(NodeId peer_id) const EXCLUSIVE_LOCKS_REQUIRED(!m_txreconciliation_mutex)
138    {
139        AssertLockNotHeld(m_txreconciliation_mutex);
140        LOCK(m_txreconciliation_mutex);
141        auto recon_state = m_states.find(peer_id);
142        return (recon_state != m_states.end() &&
143                std::holds_alternative<TxReconciliationState>(recon_state->second));
144    }
145};
146
147TxReconciliationTracker::TxReconciliationTracker(uint32_t recon_version) : m_impl{std::make_unique<TxReconciliationTracker::Impl>(recon_version)} {}
148
149TxReconciliationTracker::~TxReconciliationTracker() = default;
150
151uint64_t TxReconciliationTracker::PreRegisterPeer(NodeId peer_id)
152{
153    return m_impl->PreRegisterPeer(peer_id);
154}
155
156ReconciliationRegisterResult TxReconciliationTracker::RegisterPeer(NodeId peer_id, bool is_peer_inbound,
157                                                          uint32_t peer_recon_version, uint64_t remote_salt)
158{
159    return m_impl->RegisterPeer(peer_id, is_peer_inbound, peer_recon_version, remote_salt);
160}
161
162void TxReconciliationTracker::ForgetPeer(NodeId peer_id)
163{
164    m_impl->ForgetPeer(peer_id);
165}
166
167bool TxReconciliationTracker::IsPeerRegistered(NodeId peer_id) const
168{
169    return m_impl->IsPeerRegistered(peer_id);
170}
171

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

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